Method and means providing buoyancy of immersed crafts and crafts incorporating such means

ABSTRACT

A buoy adapted to aid in the location of a submerged craft comprising an open-bottomed normally flooded buoyancy chamber, a case enclosed in said chamber containing a gas-producing substance used to displace the water in said chamber upon release, and another casing also enclosed in said chamber containing a signal transmitter. Both of said casings are partially expansable to permit a balance of fluid pressures to prevent crushing the buoy at extreme ocean depths.

United States Patent 605,231 6/1898 Matignon Inventor James Basset Brauais par Proue, Eure-&-L0ir, France Appl. No. 844,791 Filed July 25, 1969 Patented Oct. 19, 1971 1 Priority Apr. 25, 1969, June 19, 1969 France 6913192 and 6920629 k METHOD AND MEANS PROVIDING BUOYANCY 0F IMMERSED CRAFTS AND CRAFTS INCORPORATING SUCH MEANS 1 Claim, 4 Drawing Figs.

Manama; Pingree et al Weber Alager et al.

Harada et al.

Barrett et al.

Primary Examiner-Milt0n Buchler Assistant ExaminerGregory W. OConnor Attorney-Young & Thompson ABSTRACT: A buoy adapted to aid in the location of a submerged craft comprising an open-bottomed normally flooded buoyancy chamber, a case enclosed in said chamber containing a gas-producing substance used to displace the water in said chamber upon release, and another casing also enclosed in said chamber containing a signal transmitter. Both of said casings are partially expansable to permit a balance of fluid pressures to prevent crushing the buoy at extreme ocean depths.

PATENTEDUBT 19 I97! I 3,613,616

A um rat by/Qm7. r (7% METHOD AND MEANS PROVIDING BUOYANCY F IMMERSED CRAFTS AND CRAFTS INCORPORATING SUCH MEANS under the pressure prevailing at the depth of immersion upon release of a chemical reaction obtained with a solid or liquid product or else upon starting of the combustion of a pyrotechnical fuse composition.

My invention allows in particular a stranded vessel to be set afloat and similarly a submarine sinking down to a dangerous depth to be speedily lightened.

it leads also to the execution of signalling buoys retaining a positive buoyancy whatever may be the depth, say even 10,000 meters down to which they have sunk.

As a matter of fact, it is of interest to ascertain accurately and within a time as short as possible the location of a submarine or craft or else of an aircraft which may have sunk into the water down to a considerable depth, chiefly in the case of a machine propelled by nuclear energy or carrying loads which may be dangerous for the surrounding area.

The principle of my invention is applicable to the lightening of immersed crafts such as distressed submarines and also to the setting afloat of shipwrecks.

It has already been attempted to produce an autonomous fluidtight apparatus adapted to float at midwater, said ap paratus enclosing automatic locating means. However, if it is desired to produce a chamber adapted to resist the pressure of deep waters, say when lying under 10,000 meters of water, it is impossible to obtain a positive buoyancy capable of raising, in addition to the weight of the chamber, an arrangement ensuring an automatic signalling, even if a considerable straining of the compressed walls is granted, of say 150 kg./sq. mm.

Another arrangement which has been proposed hitherto for submarine exploring apparatus providesfor the buoyancy of a system associated with a float enclosing a liquid which is lighter than water such asa hydrocarbon, the rough buoyancy per liter being then equal to the difference between the specific weights of the light liquid and of sea water. However such arrangements have let to the production of very bulky and brittle apparatus.

Similarly the buoyancy of a submarine sinking fortuitously down to a dangerous depth could be restored by driving the water out of the water ballasts by means of compressed air passing out of storing containers which latter show however the drawback of being heavy and of having a limited output.

In contradistinction, my invention solves perfectly the problem of the buoyancy of a vessel, buoy, shipwreck or the like body immersed at any depth whatever, the solution consisting in replacing when required the water carried in a compartment of such a body or in a chamber opening downwardly while its upper part remains watertight, by an equal volume of gas subjected to the water head at the depth of immersion. Said gas is produced by the fortuitous or automatic release of I I a chemical reaction between solid or liquid products or else by the combustion of a pyrotechnical composition as disclosed hereinafter. The replacement of the water driven out by an equal volume of compressed gas generates thus the rising force required in the case considered.

My invention is applicable to the setting afloat of shipwrecks wherein compartments have remained fluidtight in their upper sections so that they may be filled with gas in ac -cordance with the above-disclosed method.

My invention allows an almost instantaneous lightening of a submarine which has sunk to a dangerous extent, the lightening being obtained by introducing into the water ballasts a plurality of gas generating emergency elements as disclosed hereinafter.

In the case of a buoy provided with a positive buoyancy, said buoy may remain preferably attached to the derelict vessel by means of a cable of a short length holding the buoy under sea surface in a position allowing the production of signals by the wreck locating transmitter carried by the buoy.

By way of example of an application of my invention, l have illustrated in the accompanying drawings a signalling buoy for submarines which buoy is bestowed with a positive buoyancy at all depths of immersion, whereby the location of the associated derelict ship may be defined accurately.

I have also illustrated means for the lightening of a submarine. In said drawings:

FIG. 1 is a vertical cross section of the buoy incorporating my invention.

FIG. 2 illustrates diagrammatically a buoy of a different shape.

FIG. 3 illustrates diagrammatically a buoy connected through a cable with a stranded submarine.

H6. 4 illustrates diagrammatically a submarine of which the water ballasts are adapted to carry gas-generating emergency elements.

FIG. 1 illustrates, by way of example, a signalling buoy adapted to operate at a considerable depth and constituted by a substantially cylindrical case 4 which is subjected only to reduced difference in pressure, say 4 to 5 bars, said case enclosing an empty inner space 4A defining the useful volume of the buoy. The case 4 is fluidtight in its upper section while its lower end is fully open as provided by the ports ll and 13 which are protected by grids.

When the buoy sinks within the sea, the water enters through said ports 11 and 13 so that it fills the space'4A and compresses the air in the latter to make it reach the pressure corresponding to the actual depth at which the buoy has sunk. lf the buoy returns to sea level, the water remaining inside the space 4A flows out freely through the same ports ll and 13 and is replaced by air inside the case.

The upper end of the case 4 carries a fluidtight box 3 enclosing a supersonic transmitter with all its electrical auxiliaries such as batteries, relays and all the instruments required for the operation of the buoy.

The fluidtight box 3 located at the upper end of the case and which encloses a transmitter of supersonic waves or a wireless set as disclosed hereinafter is entirely filled with an insulating liquid preferably degased constituted by oil or petroleum for instance and bathing all the parts carried inside the box, which is sealed after the filling has been executed. The box includes at one end a bellow-shaped corrugated wall 6 which ensures through its deformation a compensation of the compression or expansion of the whole system subjected to differences in temperature and also to the pressure of water when the buoy is immersed, this corrugated wall ensuring constant equality between the inner pressure in the box and the pressure of sea water at the depth at which the buoy has sunk. in the central area of the buoy there is secured a fluidtight enclosure 9 which is entirely filled by a charge of a fuse composition 8 or by a chemical compound adapted to react when subjected to an electric priming. The whole system is made compact under an isostatic pressure of say 2,000 bars, as is generally the case for instance for the propelling charges of rockets. The enclosure 9 includes a corrugated section 10 forming bellows whereby it is possible to make up for minor modifications in volume ascribable to heat expansion or to the compression of the completely sealed system. The upper section of the enclosure 9 includes sectors or covers 7 welded fluidtightly together and adapted to be torn off when the charge 8 is ignited and releases the gases. It is apparent that if the fuse composition is fired or a suitable chemical compound is caused to react, the combustion gases flow out at 7 and fill the whole chamber 4A in the substantially cylindrical case whereby the sea water is urged out through the openings 11 and 13. At the end of the combustion, if the amount of fuse composition or the like gasgenei'ating product has been accurately reckoned the entire chamber 4A may be filled with gas under a pressure cor- The compressed gas taking the place of sea water and of the material which has produced it bestows the buoy with a buoyancy which allows it to carry, when floating, its own weight together with that of all the parts carried by it, the rough buoyancy per liter being equal to the difference between the specific weight of the compressed gas and that of the sea water which said gas replaces.

By way of exemplification under a pressure of 1,000 bars, that is about 10,000 meters of water, the specific weight of the gases obtained through combustion may be of a magnitude of 300 grams per liter at 4 C., which means that the rough buoyancy of a magnitude of 700 grams per liter of useful capacity in the buoy and a buoy of a useful capacity of 40 liters may cause the floating of a total weight of 28 kilograms when immersed at a depth of 10,000 meters.

if it is preferred to resort as disclosed hereinabove to a chemical reaction producing hydrogen, in such a case the buoyancy of the buoy reaches 38 kilograms.

The gases produced by a pyrotechnical combustion or a chemical reaction may be hot and cooled only partly during their emersion. In order that the cooled gas may occupy the useful volume which has been reckoned for cool conditions, the case 4 extends downwardly to form a skirt 12 which provides an additional volume 48 to be occupied by the expanded hot gases which upon cooling occupy entirely the sole useful space 4A.

The production of hot gases would risk damaging the fittings of the box 3. The latter is thus protected, the recess housing it leaving a free space or jacket 5 round said box, while channels 2 afford a passageway for the sea water which flows freely through the said jacket 5 so as to prevent the box from becoming too hot.

The sea water entering the case escapes freely through the ports 11 and 13 and therefore the case 4 of the buoy is subjected merely to very reduced differences in pressure. Said case may therefore be very thin walled and light, the buoyancy being associated chiefly with the supersonic or wireless transmitter in the box 3 and with the electric implementing together with the means driving the cable 14.

The buoy is secured to the submarine for instance through pins or bolts adapted to be broken by explosive charges 17 of a known type which may be released voluntarily or else automatically by an electric system carried in the box 3 as described for instance in my copending U.S. Pat. application Ser. No. 809,912.

The buoyancy of the buoy is preferably reckoned so that when released the buoy carries along with it the cable 14 to stretch it, said cable being coiled within a recess 15 at the lower end of the case. The cable 14 is short and holds the buoy attached to the sunk submarine or ship while constraining the parts of the buoy to remain in a position suitable for the transmission of signals, whatever may be the location of the stranded vessel at the bottom of the sea (FIG. 3).

The cable may possibly incorporate an electric lead through which the buoy may be released purposely by control means located inside the stranded vessel.

When the cable is cut off, the buoy may rise up to sea level and operate as a beacon providing an indication as to the area wherein the submarine has sunk, the supersonic transmission being superceded then by a wireless signalling.

The box 3 carries manometric means of a known type controlling the automatic release of the buoy as soon as the submarine sinks down to a dangerous depth through the closing of the electric circuit controlling said release through a firing of the explosive charge 8, preferably with a delay for said firing so as to give the vessel time for it to sink onto the bottom of the sea.

The buoy may be given any desired shape beyond that described say that illustrated in FIG. 2 which raises the thrust center above the center of gravity so as to ensure a better stability of the buoy as to position.

In the case of buoys intended for use with submarines and in order to reduce the weight of the battery carried inside the box 3, it is of interest to produce extremely short supersonic signals of a considerable instantaneous energyfFor instance,

the gnals may last one m6555511155?azeaaa'aia be spaced by intervals of nine hundred ninety-nine-thousandths during which the transmitters is reloaded which produces a signal 1 1,000 times more powerful than in the case of a continuous hydrogen in accordance with the formula CaH,+H,%

CaO+2H which leads to the production of 950 liters of hydrogen per kilogram of hydride, the specific weight of which is 1.2. It is also possible to use lithium or strontium hydrides but their price is very high. In fact I kilogram of lithium hydride produces 700 liters of hydrogen.

If a pyrotechnical composition is used, it is of advantage to resort to fuse compositions producing a maximum amount of gases which are not soluble in water nor condensable when compressed under ambient temperature conditions such as H,

N, CO and 0. It is thus possible to resort to the combustion of nitroguanidine in the presence of a nitrocellulosic gel,

' mitigated possibly by centralite as well known in the art, said explosive releasing 862 liters of useful gases per kilogram in accordance with the formula CH4N402 H2O CO-l-H2+2 Another example of the application of the invention to submarines is illustrated in FIG. 4 showing emergency charges of calcium hydride adapted to be distributed in the water ballasts. If the submarines sinks down to a dangerous depth, the scattering of said charges within the water of the water ballasts is obtained through any suitable means such as a small explosive charge; the hydrogen in statu nascendi which is in a compressed condition drives thus out in an exceedingly short time a corresponding volume of water which allows the stranded vessel to rise up to sea level.

By way of example at a depth of 400 meters, an emergency charge of 600 kilograms of lithium hydride entering the water ballasts leads to an almost instantaneous lift of 15 tons, this being independent of the gaseous injections produced by the conventional equipment of the vessel.

If the water ballasts are subdivided as illustrated at 21, the partial release of the hydride charges allows the vessel's trim which has been momentarily jeopardized to be restored, even if its conventional equipment is no longer operative.

The principle of my invention may be applied also to the refloating of a ship, this being obtained by generating gases in a number of compartments including upper fluidtight sections. This restores enough buoyancy for the stranded vessel to rise up to sea level, which is obtained much more speedily and more economically than if compressed air were to be injected into such compartments according to conventional practice.

The wreck-locating buoy described hereinabove for vessels stranded at great depths has been disclosed merely by way of exemplification of my invention and the distribution of the parts inside the buoy, the shape of the latter as well as the arrangement of the gas-generating charges with reference to the water ballasts of a submarine have also been disclosed without this limiting by any means the scope of my invention as defined by the accompanying claims.

What 1 claim is:

1. An equipment for buoys, submarines, and the like objects liable to sink down to a dangerous depth comprising at least one chamber, the lower end of which is fully and permanently open, a first partly expansible enclosure carried entirely within said chamber, said first enclosure carrying a gas-generating charge and having normally covered openings adapted to be opened by the pressure of the gas evolved within said first enclosure, a second partly expansible enclosure within said chamber an insulating liquid body filling entirely said second enclosure, and a signalling transmitter immersed in said liquid and adapted to operate at a predetermined momen t. 

1. An equipment for buoys, submarines, and the like objects liable to sink down to a dangerous depth comprising at least one chamber, the lower end of which is fully and permanently open, a first partly expansible enclosure carried entirely within said chamber, said first enclosure carrying a gas-generating charge and having normally covered openings adapted to be opened by the pressure of the gas evolved within said first enclosure, a second partly expansible enclosure within said chamber an insulating liquid body filling entirely said second enclosure, and a signalling transmitter immersed in said liquid and adapted to operate at a predetermined moment. 